Proximity-focused image intensifiers are a mature technology. Improvements to the size and weight of these devices have been incremental over the last couple of decades.
Conventional image intensifiers are manufactured as individual units (i.e., one at a time), using labor-intensive processes that are prone to errors in component alignment, component manufacture, and spacing, and that are prone to exposure to contaminants, which can render an entire unit unusable. Moreover, resultant image intensifiers are relatively large and heavy.
FIG. 1 shows an example of an image intensifier in the prior art. During fabrication, the majority of the parts are processed individually, although the components can be processed as groups, such as described in U.S. Pat. No. 6,086,944. This type of individual device manufacturing process is a holdover from the manufacturing model used for intensifier manufacturing in the 1970's, primarily due to the geometry of the components. Techniques for manufacturing microchannel plates (MCPs) in a wafer scale format to improve the manufacturing process for that component is provided in U.S. Pat. No. 7,109,644, and techniques for individualizing the MCP before processing the final device is provided in U.S. Pat. No. 7,126,263.
Disadvantages of constructing image intensifiers based on prior art techniques include labor intensive processes in which devices are built one-at-a-time, and in which spacing/alignment of components are difficult to control. Additionally, the intensifier device is often large and heavy, and small particles introduced during fabrication can cause the entire device to become inoperable.
Accordingly, conventional image intensifiers are not suitable for modern wafer scale fabrication technologies.